Electronic navigation products for use in the outdoors are becoming increasingly common. Typically, such products use Global Navigation Satellite Systems (GNSS) such as Global Positioning System (GPS) and GLONASS, which require the ability to read signals from orbiting satellites. However, such signals may not be readable from indoor locations. Thus, GNSS systems typically do not work well for navigation in indoor environments, such as tunnels, shopping malls, parking garages, and the like.